Monday, 9 March 2015

Pond life in the winter- Pond skaters and Water boatman

Pond skaters- Pond skaters do not spend all their time on the water, in autumn they will fly far away from the water to hibernate through the winter. The Pond skaters will emerge from hibernation in the warm spring. I watch them with amazement as they eat their prey (normally flies or insects). They stand on the water patiently until a fly or some kind of insect falls in the water and then they will jump on the prey and start demolishing their victim. But how do they know that an insect has fallen in the pond so far away???? They can sense the vibrations and ripples on the water when some thing falls or flies in it!!

Common Pond Skater eating an ant!

Water boatman- In winter most of these insects can survive, even under a thick layer of ice. They row very slowly under the ice looking for a trapped air bubble. They fill up their own air supply with the air of a bubble and then dive down to the bottom. When the water gets really cold they will still survive, in fact in one way it is better for them in the winter!?why? Because the ice cold water contains more oxygen. The bubbles are also normally larger in winter than summer. According to some people, if water boatman freeze they can simply thaw out and start swimming around again in spring!